Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 341 [Rate centres in NPA 341] [Dial plan for NPA 341]

NXX: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
341-255 A Oakland: Berkeley DA CA MLPTCAVPAMD  0051 SHELCOMM 722   2024-11-01   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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